content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2012, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
   * Other names may be trademarks of their respective owners.]
   *
   * -------------------
   * ArrayUtilities.java
   * -------------------
   * (C) Copyright 2003-2012, by Object Refinery Limited.
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   -;
   *
   * $Id: ArrayUtilities.java,v 1.7 2008/09/10 09:21:30 mungady Exp $
   *
   * Changes
   * -------
   * 21-Aug-2003 : Version 1 (DG);
   * 04-Oct-2004 : Renamed ArrayUtils --> ArrayUtilities (DG);
   * 16-Jun-2012 : Moved from JCommon to JFreeChart (DG);
   *
   */
  
  package org.jfree.chart.util;
  
  import java.util.Arrays;
  
  /**
   * Utility methods for working with arrays.
   */
  public class ArrayUtilities {
  
      /**
       * Private constructor prevents object creation.
       */
      private ArrayUtilities() {
      }
  
      /**
       * Clones a two dimensional array of floats.
       *
       * @param array  the array.
       *
       * @return A clone of the array.
       */
      public static float[][] clone(final float[][] array) {
  
          if (array == null) {
              return null;
          }
          final float[][] result = new float[array.length][];
          System.arraycopy(array, 0, result, 0, array.length);
  
          for (int i = 0; i < array.length; i++) {
              final float[] child = array[i];
              final float[] copychild = new float[child.length];
              System.arraycopy(child, 0, copychild, 0, child.length);
              result[i] = copychild;
          }
  
          return result;
  
      }
  
      /**
       * Returns <code>true</code> if all the references in <code>array1</code>
       * are equal to all the references in <code>array2</code> (two
       * <code>null</code> references are considered equal for this test).
       *
       * @param array1  the first array (<code>null</code> permitted).
       * @param array2  the second array (<code>null</code> permitted).
       *
       * @return A boolean.
       */
      public static boolean equalReferencesInArrays(final Object[] array1,
                                                    final Object[] array2) {
          if (array1 == null) {
              return (array2 == null);
          }
          if (array2 == null) {
              return false;
          }
          if (array1.length != array2.length) {
              return false;
          }
          for (int i = 0; i < array1.length; i++) {
              if (array1[i] == null) {
                  if (array2[i] != null) {
                      return false;
                  }
              }
              if (array2[i] == null) {
                  if (array1[i] != null) {
                      return false;
                  }
              }
              if (array1[i] != array2[i]) {
                  return false;
              }
          }
          return true;
      }
  
      /**
       * Tests two float arrays for equality.
       *
       * @param array1  the first array (<code>null</code> permitted).
       * @param array2  the second arrray (<code>null</code> permitted).
       *
       * @return A boolean.
       */
      public static boolean equal(final float[][] array1,
                                  final float[][] array2) {
          if (array1 == null) {
              return (array2 == null);
          }
  
          if (array2 == null) {
              return false;
          }
  
          if (array1.length != array2.length) {
              return false;
          }
  
          for (int i = 0; i < array1.length; i++) {
              if (!Arrays.equals(array1[i], array2[i])) {
                  return false;
              }
          }
          return true;
      }
  
      /**
       * Returns <code>true</code> if any two items in the array are equal to
       * one another.  Any <code>null</code> values in the array are ignored.
       *
       * @param array  the array to check.
       *
       * @return A boolean.
       */
      public static boolean hasDuplicateItems(final Object[] array) {
          for (int i = 0; i < array.length; i++) {
              for (int j = 0; j < i; j++) {
                  final Object o1 = array[i];
                  final Object o2 = array[j];
                  if (o1 != null && o2 != null) {
                      if (o1.equals(o2)) {
                          return true;
                      }
                  }
              }
          }
          return false;
      }
  
      /**
       * Compares the initial elements of two arrays.
       *
       * @param a1  array 1.
       * @param a2  array 2.
       *
       * @return An integer showing the relative ordering.
       */
      public static int compareVersionArrays (Comparable[] a1, Comparable[] a2)
      {
        int length = Math.min (a1.length, a2.length);
        for (int i = 0; i < length; i++)
        {
          Comparable o1 = a1[i];
          Comparable o2 = a2[i];
          if (o1 == null && o2 == null)
          {
            // cannot decide ..
            continue;
          }
          if (o1 == null)
          {
            return 1;
          }
          if (o2 == null)
          {
             return -1;
          }
          int retval = o1.compareTo(o2);
          if (retval != 0)
          {
            return retval;
          }
        }
        return 0;
      }
  
  }
  